Automatic firearm.



P. MAUSER, DECD.

r. EICHHORN. ADMlNlSTRATOR.

AUTOMATIC FIREARM.

APPLICATION FILED FEB. 12. I914.

PAUL MAUSER, OF OBERNDORF-ON-THE-NECKAR, GERMANY; FRIEDRICH EICHI-IORN,

OF OBERNDORF-ON-THE-NECKAR, GERMANY, ADMINISTRATOR OF SAID MAUSER,

DECEASED.

AUTOMATIC FIREARM.

Specification of Letters Patent.

Patented Nov. 2, 1915.

Application filed February 12. 1914. Serial No. 818,235.

To all whom it may concern:

Be it known that 1, PAUL MAUSER, subject of the King of ,Vurttemberg, residing at Oberndorf-on-the-Neckar, VVurttemberg, Germany, have invented new and useful Improvements in Automatic Firearms, of which the following is a specification.

The invention relates to a breech mechanism for automatic firearms, comprising a rotary breech member provided with locl zing lugs, and consists mainly in the combination of the rotary breech member with a locking member which, in the closed position, engages one of the locking lugs, thereby locking the breech member against rotation, and which, on firing, is automatically released or moved from its locking position, whereby the breech member is free to rotate and to open the breech.

The accompanying drawing shows by way of example an embodiment of the invention, in which:

Figure 1 is a vertical longitudinal section through the parts when the breech is closed and locked, the shoulder of the locking member engaging the lug of the breech member being shown in dotted lines. Fig. 2 is a vertical cross section taken on line AA of Fig. 1. Fig. 3' is a horizontal section through the parts in the same osition as shown in Fig. 1. Fig. 4-. is a vertical longitudinal section through the front portion of the breech casing. Fig. 5 is a detail view of the end portion of the locking member, in front and side elevation. Fig. 6 shows the cooperation of the locking member with the firing mechanism in side elevation.

Referring to the drawing, the breech mainly consists of the longitudinally displaceable breech bolt is, the breech closing spring 7, and the bolt head 1: located rotatably in the said breech-bolt and carrying the locking lugs w. The breech casing 72., receiving the barrel 6, is provided with notches or recesses in the usual manner, the shoulders 71 of which are engaged by the lugs w thereby closing the breech.

closure the screwing in of the lugs behind As shown in the drawing, the lugs wand the corresponding shoulders 15 are relatively beveled in such a manner that during firing the said lugs can be withdrawn from the recesses formed in the breech casing, partly owing to the recoil action and partly owing to the remaininggas pressure, and during the shoulders of the notches can take place owing to the pressure exerted by the breech closing spring 7. v

In order to positively lock the breech bolt in the closed position, a separate locking member is provided in conjunction with the said breech mechanism is, v, w, as the locking lugs are of too steep a pitch to elfect positive locking by themselves; the effect of the said locking member being to hold the breech block against rotation, i. e. to retain the bolt head 2; and its lugs 10 against backward r0- tation in the closed position until the shot is fired and the gas pressure in the barrel 6 is reduced to the degree admissible for a safe opening. i

In the constructional form illustrated, the locking member is a slide 8 displaceable in the direction of the movement of the breech bolt is within the wall of the breech casing it, so that as soon as the locking lugs have attained the closing position, it also reaches the closed position in a suitable manner and preferably under the action of a spring 9. It is obvious that the movement may also be effected positively from a moving member of the breech.

The locking takes place by the direct cooperation of the locking slide with the looking lugs, and, to this end, this slide is provided, at its front end, with an inner shoulder t, which, in the locked position, is disposed behind or beneath one of the locking lugs w (the upper) and thus prevents the bolt head 11 from rotating. In this locking position the slide 8 is located in its rear position as shown in Fig. 3. When the shot is fired, the slide 8 by its inertia moves forward, against the action of its spring 9, relative to the breech bolt k so that the previously retained locking lug w can effect its releasing rotation past the shoulder 16 of the slide 8. It is merely a matter of construction to select the ratios of these parts in such a manner that this releasing rotation and the release of the breech bolt only takes place when the requisite minimum gas pressure is attained. When closing, the converse operation takes place. When the rotation of the bolt head begins, the slide 8 with its shoulder t bears, at the front, on the lug w. The latter screws past the shoulder t inwardly into the recess formed in the sleeve lt,'until finally the lower edge of the lug is located over the upper edge of the shoulder t, at this moment the rearward path for the spring controlled slide 8 is free;

lug whereby the shoulder at is located beneath and at the rear of the lug: In order to facilitate the'operation of the lug and the shoulder, their cooperating edges are formed, as. shown in Figs. 1 and 5, with a slightly beveled edge w and t respectively.

For the purpose of insuring safety, provision is preferably made so that the slides will lock the trigger mechanism, as long as the bolt head is not locked. This can be accomplished as shown in Figs. 3 and 6by means of a lever l provided with a pin Z -engaging a curved guide 8 of the slide 8 and cooperating'in any known manner with the trigger mechanism (not shown). In this manner firing is impossible until the lug w has completely reached the closed position, and only after this is the case, does the looking slide 3 rock the lever l in that position in which it releases the trigger mechanism.

What is claimed is 1. A breech mechanism for automatic firearms comprising a rotary breech member provided with locking lugs and a member for locking said breech member whichin tr e closed position engages one of the locking lugs thereby locking the breech member against rotation, and which-locking member on firing is automatically released from its locking position so. that the breech member is free to rotate and to open the breech.

2. A breech mechanism for automatic firearms comprising a rotary breech member provided with looking lugs and a slide for locking said breech member, a spring for holding said slide in the closed position in which it engages one of the locking lugs thereby locking the breech member against rotation and which locking slide on firing is automatically released from its locking position by itsinertia against the action of its spring so that the breech member is free to rotate and to open the breech.

In witness whereof, I have 1 hereunto signed my name in-the presence of two subscribing witnesses.

v PAUL MAUSER.

Witnesses:

WOLDEMAR HAUPT, HENRY HASPER. 

